on your answer.

Phylum Porifera: Sponges

1. Adult sponges are sessile, meaning
    a.) they are considered a plant-animal.
    b.) they are essentially a water-filtering system.
    c.) they are attached to something else, not free to move about.

2. Sponges are grouped into four different classes, according to
    a.) their skeletal structure.
    b.) their ecological habitat.
    c.) whether reproduction is sexual or asexual.

3. In most sponges, sexual reproduction
    a.) involves fragments that break off from the parent animal.
    b.) involves gemmules (collections of amoebocytes).
    c.) is internal.

Radially Symmetrical Animals

1. The gastrovascular cavity of radially symmetrical animals is
    a.) the region of the body where circulation takes place.
    b.) the gelatinous layer located in the middle of the body.
    c.) where enzymes breakdown food.

2. The two shapes of Cnidarians are
    a.) polyp and medusa.
    b.) ectoderm and endoderm.
    c.) comb and walnut.

3. The class Anthozoa includes what type(s) of animals?
    a.) sea walnuts and comb jellies
    b.) jellyfish
    c.) sea anemones and coral

Bilaterally Symmetrical Animals

1. Bilateral animals are all triploblastic, meaning they have three embryonic tissue layers known as
    a.) sensory cells.
    b.) germ layers.
    c.) the coelem.

2. Examples of coelomates are
    a.) flatworms.
    b.) mollusks.
    c.) annelids.

3. The coelom possessed by coelomates develops within the
    a.) mesoderm.
    b.) digestive cavity.
    c.) endoderm.

Phylum Platyhelminthes: Flatworms

1. All flatworms are
    a.) parasitic.
    b.) the cause of schistosomiasis.
    c.) acoelomate.

2. All of the approximately 5,000 species of tapeworms
    a.) are endoparasitic.
    b.) are of the class Turbellaria.
    c.) affect only animals, such as dogs.

3. Most flatworms are parasitic, EXCLUDING the free-living class
    a.) Turbellaria
    b.) Trematoda
    c.) Cestoda

Other Acoelomates

1. The worms within the phylum Gnathostomulida are unique because of their
    a.) coastal habitat.
    b.) hard jaws.
    c.) lack of coelem or pseudocoelem.

2. In the phylum Rhynchocoela, a proboscis is
    a.) another term for the digestive cavity.
    b.) a pair of hard jaws.
    c.) a long, retractile, slime-covered hollow tube.

3. The two-opening digestive tract found in the phylum Rhynchocoela, is more efficicent that a one-opening tract because
    a.) eating can be continuous.
    b.) various stages of the tract can become specialized.
    c.) both a and b.
    d.) none of the above.

Pseudocoelomates

1. The pseudocoelom is
    a.) a protective outer coating found only on pseudocoelomates.
    b.) a fluid-filled cavity.
    c.) a structure housing the egg during reproduction.

2. The phylum Nematoda includes _________ worms.
    a.) roundworms
    b.) horsehair
    c.) tiny, burrowing marine

3. The digestive system of Entoprocta is in the shape of a
    a.) U
    b.) C
    c.) S

Phylum Mollusca: Mollusks

1. All mollusks have a head-foot, a visceral mass, a radula, and a(n)
    a.) open circulatory system.
    b.) mantle.
    c.) shell.

2. Some common examples from the class Bivalvia are
    a.) octopuses, squids, and cuttlefish.
    b.) clams, oysters, and mussels.
    c.) snails, slugs, and periwinkles.
    d.) flatworms, tapeworms, and endoparasites.

3. Some common examples from the class Cephalopoda are
    a.) octopuses, squids, and cuttlefish.
    b.) clams, oysters, and mussels.
    c.) snails, slugs, and periwinkles.
    d.) flatworms, tapeworms, and endoparasites.

4. Some common examples from the class Gastropoda are
    a.) octopuses, squids, and cuttlefish.
    b.) clams, oysters, and mussels.
    c.) snails, slugs, and periwinkles.
    d.) flatworms, tapeworms, and endoparasites.

Phylum Annelida: Segmented Worms

1. The segments of the body of an annelid are called
    a.) setae
    b.) parapodia
    c.) metameres

2. An earthworm has how many pairs of hearts?
    a.) three
    b.) two
    c.) five

3. The class Hirudean includes what common animals?
    a.) leeches
    b.) earthworms
    c.) ringworms